jQuery.extend({
    createUploadIframe: function(id, uri){
        //create frame
        var frameId = 'jUploadFrame' + id;
        var iframeHtml = '<iframe id="' + frameId + '" name="' + frameId + '" style="position:absolute; top:-9999px; left:-9999px"';
        if(window.ActiveXObject){
            if(jQuery.browser.version=="9.0" || jQuery.browser.version=="10.0"){
                var io = document.createElement('iframe');
                io.id = frameId;
                io.name = frameId;
            }else if(jQuery.browser.version=="6.0" || jQuery.browser.version=="7.0" || jQuery.browser.version=="8.0"){
                var io = document.createElement('<iframe id="' + frameId + '" name="' + frameId + '" />');
                if(typeof uri== 'boolean'){
                    io.src = 'javascript:false';
                } else if(typeof uri== 'string'){
                    io.src = uri;
                }
            }
        }
        iframeHtml += ' />';
        jQuery(iframeHtml).appendTo(document.body);
        return jQuery('#' + frameId).get(0);
    },
    createUploadForm: function(id, fileElementId, data){
        //create form
        var formId = 'jUploadForm' + id;
        var fileId = 'jUploadFile' + id;
        var form = jQuery('<form  action="" method="POST" name="' + formId + '" id="' + formId + '" enctype="multipart/form-data"></form>');
        if(data){
            for(var i in data){
                jQuery('<input type="hidden" name="' + i + '" value="' + data[i] + '" />').appendTo(form);
            }
        }
        //single
        if(typeof(fileElementId) == 'string'){
            fileElementId = [fileElementId];
        }
        for(var i in fileElementId){
            var oldElement = jQuery('#' + fileElementId[i]);
            var newElement = jQuery(oldElement).clone();
            jQuery(oldElement).attr('id', fileId);
            jQuery(oldElement).before(newElement);
            jQuery(oldElement).appendTo(form);
        }
        //set attributes
        jQuery(form).css('position', 'absolute');
        jQuery(form).css('top', '-1200px');
        jQuery(form).css('left', '-1200px');
        jQuery(form).appendTo('body');
        return form;
    },
    ajaxFileUpload: function(s) {

        s = jQuery.extend({}, jQuery.ajaxSettings, s);
        var id = new Date().getTime()
        var form = jQuery.createUploadForm(id, s.fileElementId, (typeof(s.data)=='undefined'?false:s.data));
        var io = jQuery.createUploadIframe(id, s.secureuri);
        var frameId = 'jUploadFrame' + id;
        var formId = 'jUploadForm' + id;
        // Watch for a new set of requests
        if ( s.global && ! jQuery.active++ ){
            jQuery.event.trigger( "ajaxStart" );
        }
        var requestDone = false;
        // Create the request object
        var xml = {};
        if ( s.global )
            jQuery.event.trigger("ajaxSend", [xml, s]);
        // Wait for a response to come back
        var uploadCallback = function(isTimeout){
            var io = document.getElementById(frameId);
            var execontent = function(){
                try
                {
                    if(io.contentWindow)
                    {
                        xml.responseText = io.contentWindow.document.body?io.contentWindow.document.body.innerHTML:null;
                        xml.responseXML = io.contentWindow.document.XMLDocument?io.contentWindow.document.XMLDocument:io.contentWindow.document;

                    }else if(io.contentDocument)
                    {
                        xml.responseText = io.contentDocument.document.body?io.contentDocument.document.body.innerHTML:null;
                        xml.responseXML = io.contentDocument.document.XMLDocument?io.contentDocument.document.XMLDocument:io.contentDocument.document;
                    }
                }catch(e)
                {
                    jQuery.handleError(s, xml, null, e);
                }
                if ( xml || isTimeout == "timeout"){
                    requestDone = true;
                    var status;
                    try {
                        status = isTimeout != "timeout" ? "success" : "error";
                        // Make sure that the request was successful or notmodified
                        if ( status != "error" )
                        {
                            // process the data (runs the xml through httpData regardless of callback)
                            var data = jQuery.uploadHttpData( xml, s.dataType );
                            // If a local callback was specified, fire it and pass it the data
                            if ( s.success )
                                s.success( data, status );
                            // Fire the global callback
                            if( s.global )
                                jQuery.event.trigger( "ajaxSuccess", [xml, s] );
                        } else
                            jQuery.handleError(s, xml, status);
                    } catch(e)
                    {
                        status = "error";
                        jQuery.handleError(s, xml, status, e);
                    }
                    // The request was completed
                    if( s.global )
                        jQuery.event.trigger( "ajaxComplete", [xml, s] );
                    // Handle the global AJAX counter
                    if ( s.global && ! --jQuery.active )
                        jQuery.event.trigger( "ajaxStop" );
                    // Process result
                    if ( s.complete )
                        s.complete(xml, status);
                    jQuery(io).unbind();
                    setTimeout(function(){
                        try{
                            jQuery(io).remove();
                            jQuery(form).remove();
                        } catch(e){
                            jQuery.handleError(s, xml, null, e);
                        }
                    }, 100);
                    xml = null;
                }
            };
            execontent();
        }
        // Timeout checker
        if ( s.timeout > 0 ){
            setTimeout(function(){
                // Check to see if the request is still happening
                if( !requestDone ) uploadCallback( "timeout" );
            }, s.timeout);
        }
        try{
            var form = jQuery('#' + formId);
            jQuery(form).attr('action', s.url);
            jQuery(form).attr('method', 'POST');
            jQuery(form).attr('target', frameId);
            if(form.encoding)
            {
                jQuery(form).attr('encoding', 'multipart/form-data');
            }else{
                jQuery(form).attr('enctype', 'multipart/form-data');
            }
            jQuery(form).submit();
        } catch(e){
            jQuery.handleError(s, xml, null, e);
        }
        jQuery('#' + frameId).load(uploadCallback );
        return {abort: function () {}};
    },
    uploadHttpData: function( r, type ) {
        var data = !type;
        data = type == "xml" || data ? r.responseXML : r.responseText;
        // If the type is "script", eval it in global context
        if ( type == "script" )
            jQuery.globalEval( data );
        // Get the JavaScript object, if JSON is used.
        if ( type == "json" )
            eval( "data = " + data );
        // evaluate scripts within html
        if ( type == "html" )
            jQuery("<div>").html(data).evalScripts();
        return data;
    },
    handleError: function( s, xhr, status, e ){
        // If a local callback was specified, fire it
        if ( s.error ) {
            s.error.call( s.context || s, xhr, status, e );
        }
        // Fire the global callback
        if ( s.global ) {
            (s.context ? jQuery(s.context) : jQuery.event).trigger( "ajaxError", [xhr, s, e] );
        }
    }
})